ROX1SF68K Equivalent & Substitute Parts

Part Overview

The ROX1SF68K is a 68 kOhms ±1% 1W through-hole resistor manufactured by TE Connectivity Passive Product in the ROX/Neohm series. This axial metal oxide film resistor features flame-proof and pulse-withstanding characteristics with a safety rating. The part is classified as obsolete, necessitating identification of equivalent substitute components for ongoing applications and new designs. Substitute parts must maintain the 68 kOhms resistance value and 1W power rating while meeting the electrical and mechanical requirements of the original specification.

Substiute Parts

ROX1SF68K

TE Connectivity Passive ProductIn Stock: 691ROX1SF68K Datasheet

Current PartRFQ

ROX1SJ68K

TE Connectivity Passive ProductIn Stock: 11019ROX1SJ68K Datasheet

SimilarRFQ

FMF1WSFRF52-68K

YAGEOIn Stock: 965FMF1WSFRF52-68K Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the ROX1SF68K is determined by the following critical parameters: resistance value (68 kOhms), power rating (1W), package type (axial through-hole), and operating temperature range compatibility. The tolerance specification (±1%) and composition type (metal oxide film) define the primary substitution category. Parts meeting these core electrical and mechanical requirements are classified as direct equivalents. Parts with relaxed tolerance specifications (±5%) or alternative film compositions (metal film) are classified as functional alternatives with noted parameter variations.

The two identified substitute parts satisfy the mandatory requirements as follows:

ROX1SJ68K: Maintains 68 kOhms resistance, 1W power rating, axial package, and metal oxide film composition. Tolerance is relaxed to ±5%. Product status is active with RoHS3 compliance.

FMF1WSFRF52-68K: Maintains 68 kOhms resistance, 1W power rating, and axial package. Composition is metal film (not metal oxide film). Tolerance is ±1%. Product status is active with RoHS3 compliance and REACH unaffected status.

Parameter Comparison

Engineering Selection Recommendations

ROX1SJ68K is the primary substitute for direct replacement in applications where the ROX1SF68K is currently deployed. This part maintains identical electrical characteristics (68 kOhms, 1W, metal oxide film composition, ±350ppm/°C temperature coefficient) and mechanical compatibility (identical axial package dimensions). The tolerance specification is relaxed from ±1% to ±5%, which is acceptable in applications where the original ±1% tolerance was not a critical design requirement. The part is manufactured by the same supplier (TE Connectivity Passive Product) and carries active product status with RoHS3 compliance, ensuring long-term availability and regulatory alignment.

FMF1WSFRF52-68K is an alternative substitute for applications where the ±1% tolerance specification must be maintained. This YAGEO part preserves the ±1% tolerance and offers superior temperature stability (±100ppm/°C versus ±350ppm/°C). The operating temperature range extends to 155°C, providing additional thermal margin. The composition differs (metal film instead of metal oxide film), and the physical dimensions are slightly smaller (0.130" Dia x 0.354" L versus 0.138" Dia x 0.394" L). This part is active with RoHS3 compliance and REACH unaffected status. The pulse-withstanding feature specified in the original part is not listed for this substitute.

Selection between these substitutes depends on tolerance requirements, thermal stability needs, and feature compatibility with the target application.

Frequently Asked Questions (FAQ)

Q: Can ROX1SJ68K be used as a direct replacement for ROX1SF68K?

A: ROX1SJ68K is functionally compatible for most applications. Both parts share identical resistance (68 kOhms), power rating (1W), composition (metal oxide film), temperature coefficient (±350ppm/°C), and axial package dimensions. The primary difference is tolerance: ROX1SJ68K is ±5% versus the original ±1%. Applications requiring strict tolerance control should evaluate this specification change.

Q: What are the physical compatibility considerations when substituting FMF1WSFRF52-68K?

A: FMF1WSFRF52-68K has slightly smaller dimensions (0.130" Dia x 0.354" L) compared to ROX1SF68K (0.138" Dia x 0.394" L). Both are axial through-hole packages with 2 terminations. The smaller size typically accommodates in existing PCB layouts designed for the original part, though verification of board-level spacing is recommended for high-density designs.

Q: How do temperature coefficients differ between the substitutes?

A: ROX1SF68K and ROX1SJ68K both specify ±350ppm/°C temperature coefficient. FMF1WSFRF52-68K specifies ±100ppm/°C, indicating superior temperature stability. Applications operating across wide temperature ranges or requiring minimal resistance drift benefit from the lower temperature coefficient of the YAGEO part.

Q: Are both substitute parts RoHS compliant?

A: Yes. Both ROX1SJ68K and FMF1WSFRF52-68K carry RoHS3 compliance certification. The original ROX1SF68K does not specify RoHS status. For applications requiring RoHS compliance, either substitute part satisfies this requirement.

Q: What is the difference between metal oxide film and metal film composition?

A: Both are resistive film types used in through-hole axial resistors. Metal oxide film (ROX1SF68K and ROX1SJ68K) typically exhibits higher pulse withstanding capability and is specified with ±350ppm/°C temperature coefficient in this product line. Metal film (FMF1WSFRF52-68K) offers lower temperature coefficient (±100ppm/°C) and tighter tolerance capability. The original part specifies pulse-withstanding as a feature; FMF1WSFRF52-68K does not list this feature.

Q: What packaging formats are available for the substitute parts?

A: ROX1SJ68K is supplied in Cut Tape (CT) format. FMF1WSFRF52-68K is supplied in Tape & Reel (TR) format. These packaging differences affect procurement quantities and handling but do not impact electrical or mechanical performance.

Q: Is the operating temperature range a limiting factor in substitution?

A: ROX1SF68K and ROX1SJ68K both specify -55°C ~ 130°C operating range. FMF1WSFRF52-68K extends to -55°C ~ 155°C. Applications operating above 130°C require FMF1WSFRF52-68K. Applications within the -55°C ~ 130°C range are compatible with all three parts.